CS中的实用程序（－）Ilist 转换到datatable

datatable在某些方面要比Ilist操作起来方便很多，尤其是修改一些老程序时，客户端已经都绑定到了Dataset或者datatable，如果让他们重新绑定到Ilist会做大量的工作。
如果能转换到Datatable会方便很多

public class CADataConverter
    {

        private static Hashtable types = new Hashtable();

        private CADataConverter()
        {
        }

        /**//// <summary>
        /// Converts an IList into a datatable.
        /// </summary>
        /// <param name="list">List of objects. First item can not be null</param>
        /// <returns></returns>
        public static DataTable ToDataTable(IList list)
        {
            if(list == null)
                throw new ArgumentNullException("list", "List can not be null");

            if(list.Count == 0)
                throw new ArgumentOutOfRangeException("list", "List can not be empty without supplying a type. Please use the other overload");

            object obj = list[0];
            if(obj == null)
                throw new ArgumentOutOfRangeException("list", "First item in collection can not equal null");


            return ToDataTable(list,obj.GetType());
        }

        /**//// <summary>
        /// Converts an IList into a datatable.
        /// </summary>
        /// <param name="list"></param>
        /// <param name="t">Since a type is supplied, the list can be null or empty</param>
        /// <returns></returns>
        public static DataTable ToDataTable(IList list, Type t)
        {
            DataTable dt = types[t] as DataTable;
            if(dt == null)
                dt = CreateShell(t);
            else
                dt = dt.Clone();

            if(list == null || list.Count == 0)
                return dt;

            foreach(object item in list)
            {
                if(item != null)
                {
                    DataRow dr = dt.NewRow();
                    foreach(DataColumn dc in dt.Columns)
                    {
                        try
                        {
                            dr[dc.ColumnName] = t.GetProperty(dc.ColumnName).GetValue(item,null);
                        }
                        catch{}
                    }
                    dt.Rows.Add(dr);
                }
            }

            return dt;
        }

        /**//// <summary>
        /// Creates a datatable with datacolumns
        /// </summary>
        /// <param name="t"></param>
        /// <returns></returns>
        protected static DataTable CreateShell(Type t)
        {
            DataTable dt = new DataTable(t.Name);
            PropertyInfo[] pia = t.GetProperties();
            foreach (PropertyInfo pi in pia)
            {
                if(pi.CanRead)
                {
                    string st = pi.PropertyType.ToString();
                    switch(st)
                    {
                        case "System.String":
                        case "System.Int32":
                        case "System.Boolean":
                        case "System.Double":
                        case "System.Guid":
                            dt.Columns.Add(pi.Name,pi.PropertyType);
                            break;
                    }
                }
            }

            types[t] = dt;

            return dt;
        }
    }

通过反射取到Type的信息，type的属性被做为列名，CreatShell 实现
类型的属性值作为行。TODatatable实现
调用：
DataTable dt = CADataConverter.ToDataTable(categories,typeof(PostCategory));